Diazotizable dye.



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CART. HEIDENREICH, OF LEVERKUSEN, NEAR COLOGNE, GERMANY, ASSIGNOR TO FAR- EENFABRIKEN 'VURM. FRI EUR. BAYER dt 00., ELBEREZELD, GERMANY, A COB/P0- narrow or easement".

lDlEOTTfidiBLE DYE.

No Drawing.

specification of Letters lPatcnt. P t nt d No 28, that, Application filed April 25, 1911. Serial No. 6%,205.

To all whom, it may concern:

Be it known that ll, CARL Hnmnnnnron, doctor of philosophy, chemist, citizen of the German Empire, residing at Leverkusen, near Gplogne, Germany, have invented new and useful Improvements in Diazotizable Dye, of which the following is a specification.

Green'substantive dyestuffs capable of being diazotized could hitherto not been obtained, though they are of great technical interest for completing the series of shades and for modifying the shades produced by other dyestuffs capable of being diazotized. ll have now succeeded in obtaining such dyes capable of dyeing cotton green to olive green shades in the following way. 1 molecule 0t atetrazotized para-diamin of the benzidin series and 1 molecule of an aromatic oirycarboirylic acid such as salicylic or cresotinic acid are combined together to form the intermediate compound which is then further combined with 1.8-aminonaphthoLt-sultonic acid-in an acid suspension. The resulting coloring matter is then combined in alkaline solution with the diazo compound prepared from acidyl-para-phenylenediamin or from para-nitranihn and finally the trisazo dyestud is saponified or the nitro group therein contained reduced. The dyestufis thus ob",

tained of the formula:

\N=N\/\\ WMN .NH!R J (ME in which formula R means an atom of hydrogen which may be substituted by the methyl group, dye cotton in green shades, which, on being diazotiz (l and deyeloped with beta-naphthol or eta-phenylenediamin, are very little changed, but are-rendered fast to Washing by this process. They are dark powders yielding upon reduction with stannous chlorid and hydrochloric acid a para-diamin of the bensidin series, an ammo-ouycarboxylic acid, 1.2.T-triamino-8- filtered oil and dried.

para-phenylcompound prepared in the usual way from 18.4 parts of benzidin and 14 parts of salicylic acid, is rendered just acid with hydrochloric acid and is introduced into an acid suspension of 24 parts of 1.8-aminonaphtholl-sulfonic acid. The mixture is stirred for. 24 hours, the free mineral acid being carefully neutralized during this operation with sodium acetate. The diazo compound ob tained in the usual way from 18 parts of para-phenylenediamin oiraminic acid is add ed to this mixture and it is then rendered distinctly alkaline with sodium carbonate solution. After 6 hours the mixture is heated to 70? C. and the dyestud is salted out and filtered 0ft, It .is then stirred up with 500 parts of waterand heated to boiling for half an hour with 120 parts of caustic soda lye containing per cent. of NaUl-l'. Edubsequently the caustic soda lye is partially neutralized and the dyestufl' is salted out, It has the formula:

/ coon and is a dark powder which is soluble iii water with a green color and dyes cotton in.

green shades which on being diaaotiaed and combined with beta-naphthol turnintoa somewhat darker green of good fastness to washing. it yields upon reduction withstannous chlorid and hydrochloric acid benzidin, para-aminosalicylic acid, 1.2.7-triamino-d-naphtholl-sulfonic acid and paraplp en ylenediamin. It is soluble in cone. sulfuric acid with a violet-blaclreolor.

Instead of benzidin other diamins can be used, such as tolidin, dianisidin etc.

I c1ain1: 1. The herein described new dyestuffs of the formula N=N-0xycarb0xylic acid SOsH ' which dyestuffs are after being dried and pulverized dark powders soluble in water and in concentrated sulfuric acid; yielding upon reduction with stanngus chlorid and hydrochloricacid a para-diamin of the benzidin series, an amino-oxy-carboxylic acid,

1.2.7-triainino-8-naphtho1-4-sulf0nic acid and para-phenylenediamin; dyeing cotton in green shades fast to washing, which can be diazotizedand developed with beta-naphthol, substantially as described.

2. The herein described new dyestuffs of the formula para-diamin NH: OH

N=N N=N NH1 l i a so n which dyestuffs are after being dried and pulverized dark powders soluble in water and in concentrated sulfuric acid; yielding upon reduction with stannous chlorid and SOaH which dyestuif is after being dried and pulverized a dark powder soluble in water with a green color and soluble in concentrated sulfuric'acid with a violet-black color; dyeing cotton in green shades which on being developed with beta-naphtholturn into a darker green of good fastness to washing; yielding upon reduction with stannous chlo-- rid and hydrochloric acid benzidin, paraaminosalicylic acid, 1.2.7-triamino-8-naphthol--sulfonic acid and para-phenylenediamin, substantially as described.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

CARL HEIDENREIOH. [L. 5.]

Witnesses:

CHAS. J. WRIGHT, ALFRED HENKEL.

' Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. 0. 

